FIELD OF THE INVENTION
[0001] The invention relates to a method and apparatus for demolding and analyzing a direct
analysis sample formed from a molten metal material contained within a sample chamber
assembly, wherein the sample chamber assembly comprises at least a sample housing,
a cover plate and closing means. The invention also relates to a system comprising
an apparatus and a direct analysis sample.
BACKGROUND OF THE INVENTION
[0002] During the metallurgical processing of iron and steel, the molten metal material
is sometimes mixed with other molten metal batches or treated to alter its chemistry
prior to being charged into a converter. Accordingly, it is advantageous to extract
a sample of the molten metal material to determine its chemical composition during
treatment and for use in mass and energy balances of the converter process and for
process control during steelmaking processes. Devices for extracting samples for chemical
analysis are well known in the art. An example of one such prior art reference is
U.S. Patent No. 3996803.
[0003] Typically, a conventional molten metal or steel sampler is a low-cost sampling device
arranged in a refractory body and mounted on a carrier tube and having an inlet for
the molten metal to enter a chamber that is formed by two thick metal chill plates.
Conventional samples have a temperature of about 500°C to 800°C when they are being
retrieved from the molten metal and need cooling before the samples can be analyzed.
Also, the analysis surfaces of conventional samples need to be prepared by grinding
prior to analysis to remove oxides from the surfaces and to provide the required flat
topography.
[0004] Whereas, a newly developed type of molten metal immersion samplers, commonly referred
to as direct analysis (DA) samplers do not require any kind of cooling, the typical
sample temperature is only around 100°C, ranging from 70°C to 130°C, when retrieved
from the molten metal bath. In addition, direct analysis samples do not require surface
preparation before they are being analyzed, which results in an economic benefit both
in terms of the availability of analyses results as well as in laboratory time savings.
[0005] For example, prior art references
EP3336513A1,
EP3336514A1,
EP3336512A1, and
EP3336511A1 relate to direct analysis samplers that do not require any sample preparation steps,
such as cooling, cleaning and grinding. Once the sample chamber assembly containing
the sample is retrieved from the molten metal, a part of the sample chamber assembly,
such as the cover plate, can be removed to expose at least part of an analysis surface
of the sample, which can be immediately analyzed.
[0006] The composition of a sample can be determined using an analysis instrument comprising
arc spark-optical emission spectroscopy equipment, also sometimes just referred to
as optical emission spectroscopy or OES on the analysis surface of the sample. Optical
emission spectroscopy systems are generally the most effective systems for determining
the chemical composition of a sample comprising metal and for controlling the processing
of molten metals due to their rapid analysis times and inherent accuracy. Thus, optical
emission spectroscopy analysis is typically used during molten metal processes for
controlling the progress of molten metal production.
[0007] When a sample chamber assembly is opened manually to expose the analysis surface,
there is a high risk that the analysis surface will get contaminated. The deviations
of the elements to be analyzed are mainly caused by the displacement of the cover
plate. In particular, deviations on aluminum and deviations on carbon and sulfur can
be observed. Deviations on aluminum are generally caused by mechanically contacting
the cover plate and the analysis surface. The deviations on carbon and sulfur are
caused by a more severe displacement so that part of the sealing material used to
seal the space between sample housing and the cover plate touches the analysis surface
of the sample before the sample chamber assembly is opened. Also, dirt particles and
tar deposits originating from the refractory body can be another source of contamination.
In addition, the handling of the sample chamber assemblies after demolding can be
yet another source of contamination. The handling is typically done by mechanical
tools, handled by a glove wearing operator. Therefore, it is intended to eliminate
or at least reduce the adverse effects of contamination on the analysis results. Some
analyses, such as for example end blow analyses in the Basic Oxygen Process or in
the Electric Arc Furnace require an analysis accuracy in the range of a few ppm.
[0008] Apparatuses for automatically demolding samples formed from a molten metal are already
known in the prior art. For example, prior art reference
EP2626685A1 describes a spinner device for spinning a sample contained in a sample housing against
an impact element for demolding the sample. Prior art reference
DE19852528A1 describes a cutting device which is adapted to cut a sample contained in a housing
in half for demolding the sample.
[0009] However, the apparatuses known from the prior art are not suitable for demolding
a direct analysis sample without contaminating or destroying the analysis surface
during the demolding process. Consequently, the analysis surfaces of the prior art
samples are often contaminated with dirt particles that can contaminate the analysis
instrument and can cause incorrect analysis results.
[0010] Therefore, there still exists a need for an improved apparatus and technique for
demolding and analyzing a direct analysis sample formed from a molten metal material
contained within a sample chamber assembly where the analysis surface of the sample
is kept clean and is not subject to major contamination when the sample chamber assembly
is opened to expose the analysis surface.
[0011] This need is fulfilled by the subject-matter of the independent claims.
SUMMARY OF THE INVENTION
[0012] The invention provides an apparatus for demolding and analyzing a direct analysis
sample formed from a molten metal material contained within a sample chamber assembly,
wherein the sample chamber assembly comprises at least a sample housing, a cover plate
and closing means, comprising:
a cabinet defining an interior and comprising at least one opening for the sample
housing to enter the cabinet, and analyzing means located inside the cabinet for analyzing
an analysis surface of the sample;
demolding means adapted to remove at least the closing means to expose at least part
of the analysis surface of the sample; and
transporting means adapted to hold and transport the sample housing at least between
a sample demolding position, where the closing means is removed by the demolding means,
and a sample analysis position, where the analysis surface of the sample is analyzed
by the analyzing means, and wherein the sample demolding position and the sample analysis
position are different from each other.
[0014] The sample chamber assembly can be made of a material which is a good thermal conductor,
such as copper or aluminum. The cover plate, which can also be referred to as lid,
can be made from the same material as the sample housing or from a different material
such as fused silica or a refractory ceramic material. The cover plate can have the
same width and length as the sample housing and can have a first side and an opposing
second side. The first side of the cover plate can face the sample housing in an assembled
position. A sealing member can be additionally provided on the first face of the cover
plate to be positioned between the sample housing and the cover plate in the assembled
configuration of the sample chamber assembly to provide a gas tight seal. The sealing
member can be a gasket formed of paper, silicone or any similar polymer and can be
dimensioned to encompass or surround a ridge in the assembled configuration of the
sample chamber assembly.
[0015] In the assembled configuration of the sample chamber assembly, at least the cover
plate and the sample housing are assembled together to form the sample cavity, while
being held together by the closing means, for example a clamp, brace, spring or clip
with a compression force sufficiently high to withstand the pressure of purge gas
applied prior to filling the sample cavity and to resist a tendency of the sample
housing and cover plate to separate due to the force of molten metal flowing into
the sample housing and filling the sample cavity.
[0016] When the sample cavity is filled with molten metal, the molten metal freezes against
the first side of the cover plate, thereby forming the analysis surface of the direct
analysis sample, which is the surface to be analyzed after demolding the sample.
[0017] The term "cabinet" can be used to refer to an enclosure of at least the analyzing
means that shields the analyzing means and reduces or prevents exposure of the analyzing
means to dust and dirt particles. The cabinet can have doors for ease of maintenance
and can be foreseen with acclimatization, e.g. cooling and heating, means. Also, the
cabinet comprises an opening for the sample housing to enter the cabinet space by
means of the transporting means. During stand-by operation at least part of the transporting
means can be positioned in the opening to reduce the risk of dust and dirt particles
entering the cabinet.
[0018] The term "transporting means" adapted to hold and transport the sample housing can
be used to refer to a mechanism that holds the sample housing, preferably by clamping
the sample housing between two clamps, and that transports the held sample housing
towards the inside of the cabinet for analyzing the exposed analysis surface. In addition,
the "transporting means" can be also adapted to discard the sample housing after the
analysis, for example by opening one clamp or both clamps so that the sample housing
can fall into a collection bin.
[0019] The sample demolding position can be a position outside the cabinet in which the
closing means is removed, and the analysis surface is exposed. In one example, the
demolding position can be the same position as an inserting position where the sample
housing is inserted into the transporting means. In an alternative example, the demolding
position and the inserting position can be different positions where the sample chamber
assembly or at least the sample housing is transported between the inserting position,
the demolding position, and the analysis position.
[0020] The transporting means can be realized with at least two clamps or brackets that
are mounted on a slider system such as a glide surface/track or a slide cam which
allows the clamps to slide along a predetermined path of the slider system. The transporting
means can, for example, comprise an actuator for detecting the presence of the sample
housing which can be a springloaded mechanism or an electronic sensor that causes
a relative movement of the two clamps to hold the sample housing. The transporting
means can hold the sample housing during demolding to expose at least part of the
analysis surface of the sample and transporting the sample housing towards and into
the sealed cabinet in which the analyzing means are located for analyzing the analysis
surface.
[0021] The term "demolding means" adapted to remove at least the closing means to expose
at least part of the analysis surface of the sample can be used to refer to a mechanism
that is adapted to automatically remove the closing means. In one example, the demolding
means can also penetrate the sample chamber assembly, e.g. remove or displace some
of the material of the sample chamber assembly, such as for example the cover plate,
to expose at least part of an analysis surface of the sample. For example, the demolding
means can be realized by a blade, pin, rod, piston, or by any suitable device that
can be used to remove the closing means, and/or the cover plate. For example, the
demolding means can further comprise a supporting surface on which the sample chamber
assembly can be arranged with its cover plate facing the supporting surface and being
in contact with the supporting surface. Once the closing means, e.g. a clamp, got
removed and while the sample housing is still held by the transporting means, the
supporting means can be retracted in a backward/forward, sideways, or downwards direction
to allow the cover plate to come off by means of gravity so that it can preferably
fall into a collection bin located underneath. Alternatively, or in addition the demolding
means could further comprise another blade pin, rod, piston, etc. to mechanically
remove the cover plate.
[0022] Advantageously, removal of the cover plate takes place without mechanically contacting
the analysis surface, but instead by lifting the cover plate away from the analysis
surface or letting it separate by itself once the closing means was removed. Hence,
removal of the cover plate does not cause abrasion or friction to the analysis surface
of the sample.
[0023] In an example, the transporting means can comprise an abutment surface, preferably
arranged at least in part parallel to the second clamp, to prevent movement of the
sample housing in a sideways direction.
[0024] For example, the abutment surface can be rigidly arranged, wherein the distance between
abutment surface and first clamp and/or second clamp can be chosen to match the width
of the sample housing. Advantageously, by means of the abutment surface, the sample
chamber assembly can be more easily positioned into the apparatus.
[0025] Advantageously, the invention provides an apparatus that allows demolding and analyzing
a sample in a fast and efficient way with a greatly reduced risk of contamination
of the sample's analysis surface. Also, the time between taking the sample and analyzing
the sample can be greatly reduced compared to the techniques known from the prior
art.
[0026] In an example, the demolding means comprises at least one blade arranged, preferably
moveably arranged, in at least a sideways direction or a longitudinal direction relative
to an axis formed by the demolding position and the analysis position and adapted:
- (i) to move over a surface of the sample chamber assembly to remove the closing means
of the sample chamber assembly, preferably a clamp or a brace, holding the sample
housing and the cover plate together, or
- (ii) to move over a surface of the sample chamber assembly to remove the closing means
and to penetrate the sample chamber assembly, preferably at a location between the
sample housing and the cover plate to remove the cover plate from the sample housing,
to expose at least part of the analysis surface of the sample.
[0027] Here, the term "sideways direction" can be used to refer to a direction perpendicularly
to the direction of movement of the transporting means, wherein the transporting means
can move at least between the sample demolding position and the sample analysis position.
The term "longitudinal direction" can be used to refer to a direction of movement
on an imaginary line between the sample demolding position and the sample analysis
position in the direction of movement of the transporting means.
[0028] For demolding, the blade can directly move over the surface of the sample housing
or with a distance between blade and surface of the sample housing to get hold of
at least part of the closing means and to remove it from the sample housing while
the blade moves. Additionally, the blade or another blade associated with the blade
can also penetrate the sample chamber assembly, such as moving into the material of
the sample chamber assembly to separate at least part of the sample chamber assembly
to expose the analysis surface.
[0029] Advantageously, demolding can be performed automatically without any interference
by the operator.
[0030] In one example, the demolding means comprises at least one supporting surface to
support at least a part of the cover plate of the sample chamber assembly when being
held by the sample transporting means and wherein the supporting surface is movably
arranged to allow the cover plate to separate from the sample housing by means of
gravitational force.
[0031] The supporting surface can be a surface on which the sample chamber assembly rests
when the sample chamber assembly is held for removing the closing means. The sample
chamber assembly can be loaded such that the cover plate of the sample chamber assembly
is placed on the supporting surface. Once the closing means is removed, the supporting
surface can be removed, for example by lifting, sliding or pivoting it away, so that
the cover plate can fall off to expose the analysis surface. Therefore, the supporting
surface being movably arranged can be understood as movably arranged relative to the
sample chamber assembly held by the transporting means.
[0032] In one example, the transporting means comprises: a first clamp and a second clamp
for holding the sample housing and to stop movement of the sample housing in at least
a forward and a backward direction from both the demolding position and analysis position,
wherein the first clamp and the second clamp are movably arranged in the forward and
backward direction for transporting the sample housing between the sample demolding
position and the sample analysis position, wherein the second clamp is arranged at
least in part opposite the first clamp, preferably the first clamp or the second clamp
further comprises sensor means for detecting contact of the first clamp or the second
clamp and the sample housing.
[0033] As already described above, the two clamps can be mounted on a slider system such
as a glide surface/track or a slide cam which allows the clamps to slide along the
way of the slider system. The slider system can extend from the inserting position,
e.g. a sample bay, where the sample chamber assembly can be positioned by an operator
into a space between the first clamp and the second clamp to the analysis means where
the analysis surface of the sample is analyzed. Here, the terms "forward and backward
direction" can be used to refer to a forward and backward direction along the axis
extending from the sample bay to the analysis means.
[0034] The first clamp and the second clamp can be moved on the slider system independently
from each other or can be moved together, e.g. in case the first clamp and the second
clamp are produced from one piece of material. In examples of the invention, the first
and second clamp can be moved by hand, by a mechanism, or a drive, such as for example
an electric or pneumatic drive or motor. In one example of the invention, the first
clamp located closer to the analyzing means than the second clamp comprises sensor
means, such as a contact or proximity sensor, alternatively a mechanical spring biased
mechanism can be employed, that can detect a sample housing being placed between the
first clamp and the second clamp. Upon detecting the sample housing between the first
clamp and the second clamp, at least one of the clamps or both clamps can move towards
each other to hold the sample housing, and/or locking means can be employed to hold
the sample housing.
[0035] In one example, the second clamp comprises locking means, preferably a spring biased
latch, adapted to allow the sample housing to be moved past the locking means towards
the first clamp, and to prevent movement of the sample housing in the opposite direction,
preferably the first clamp comprises another locking means, preferably another spring
biased latch, adapted to prevent movement of the sample housing in the forward and
backward direction.
[0036] The locking means can be arranged on a side surface of the second clamp facing the
first clamp, wherein the locking means can comprise a latch such as a toggle lever
or rocker lever that allows to move the sample housing towards the first clamp in
at least a horizontal plane and when the sample housing is moved past the locking
means, a spring or an actuator in the locking means can activate the lever such that
the sample housing is locked and cannot be moved back anymore. In one example, where
an actuator is used, triggering means of the actuator could be coupled to the sensor
means as described in the previous example. Upon detecting the presence of a sample
housing between the first clamp and the second clamp, the triggering means could cause
the actuator to lock the lever such that the sample housing is locked between the
first clamp and the second clamp. Alternatively, a spring which is compressed by retracting
the lever while the sample housing is moved past the lever could expand again for
moving the lever out again so that the sample housing is locked between the first
clamp and the second clamp.
[0037] Alternatively, or additionally, the locking means could also be arranged to prevent
movement of the sample housing in each spatial direction.
[0038] Advantageously, the locking means allow to easily load a sample chamber assembly
into the apparatus and to reliably hold and transport the sample housing during demolding
and analyzing.
[0039] In another example, the transporting means comprises at least one drive means, preferably
an electric motor, to move the first clamp and the second clamp comprising the locking
means and holding the sample housing in the forward direction towards the analyzing
means, preferably the transporting means comprises a first drive means for moving
the first clamp and a second drive means for moving the second clamp independently
from each other.
[0040] The clamps can be moveable, for example on a glide surface/track or a slide cam,
by means of a drive means which could be an electric motor, a mechanical system activatable
by manual force, or a pneumatic system.
[0041] In an example, the demolding means comprises actuation means for moving, preferably
sequentially moving, the blade and the supporting surface, and wherein the actuation
means comprises a hand gear for moving the blade and the supporting surface mechanically,
or a push rod for moving the blade and the supporting surface pneumatically or electrically,
between a first and a second position.
[0042] In another example, the actuation means is adapted to be moved between a first and
a second position, wherein:
in the first position, the actuation means and blade are arranged for loading the
sample housing, wherein at least the first clamp is at least partly arranged in the
opening of the sealed cabinet, and
in the second position, the actuation means and blade are arranged for analyzing the
sample by the analyzing means, wherein at least the second clamp is at least partly
arranged in the opening of the sealed cabinet.
[0043] The actuation means are adapted to be moved between the first and the second position,
wherein in the first position the actuation means is arranged for loading the sample
housing, wherein at least the first clamp is at least partly arranged in the opening
of the sealed cabinet. In the first position, the sample housing can be put between
the first and second clamps.
[0044] Moving the actuation means causes at least the demolding means to remove the closing
means. The movement also causes the supporting surface to be removed at the same time
or shortly after, or the movement causes the blade to penetrate the sample chamber
assembly, preferably at a location between the sampling housing and the cover plate
for exposing at least part of the analysis surface of the sample.
[0045] In the second position, the actuation means is arranged for analyzing the sample
by the analyzing means, wherein at least the second clamp is at least partly arranged
in the opening of the sealed cabinet. In the second position, the demolded sample
housing can be transported by means of the first and second clamp to the inside of
the cabinet for analysis, while at least the second clamp is at least partly arranged
in the opening of the cabinet. For example, the first and second clamp are both moved
towards the inside of the cabinet, wherein the first clamp is moved past the analyzing
means to position the analysis surface on top of the analyzing means, and the second
clamp is moved into the opening holding the sample housing together with the first
clamp.
[0046] Advantageously, arranging either the first clamp or the second clamp in the opening
of the cabinet in one of the two positions allows to reduce the number of unwanted
particles, such as dust, entering the cabinet, which could falsify the analysis results.
[0047] In another example, at least a first dust cover mounted on a stationary part of the
apparatus, and a second dust cover mounted on the blade or a moveable part mechanically
associated with the blade and moving together with the blade, wherein at least part
of the first dust cover and the second dust covers are arranged to be spaced apart
to allow loading the sample chamber assembly when the actuation means is in the first
position, and at least partly overlap when the actuation means is in the second position,
preferably at least one dust seal such as a brush seal is arranged on one of the first
and/or second dust covers to seal a remaining space between the first and second dust
cover when they are overlapping.
[0048] Advantageously, by employing the first and second dust cover the number of unwanted
particles, such as dust, entering the sealed cabinet can be further reduced.
[0049] In an example thereof, the first dust cover comprises an insertion-opening for inserting
the sample chamber assembly into the transporting means, and wherein the second dust
cover overlaps the insertion-opening when the actuation means is in the second position.
[0050] In another example, the analyzing means comprise an optical emission spectrometer,
preferably a spark optical emission spectrometer, more preferably a top-loaded optical
emission spectrometer comprising a spring to hold the analysis surface of the sample
at a distance to a contact electrode of the optical emission spectrometer, and adapted
to establish an electric contact to the analysis surface of the sample when the spring
is in a compressed state, most preferably a top-loaded optical emission spectrometer
comprising a spring having a force of less than 100 Newton, preferably less than 10
Newton to hold the analysis surface at a distance of preferably less than 1 mm to
the contact electrode of the optical emission spectrometer.
[0051] Optical emission spectroscopy involves exciting atoms of a target sample of which
knowledge of the composition is desired and examining the wavelength of photons emitted
by atoms during transition from an excited state to a lower energy state. Each element
in the periodic table emits a characteristic set of discrete wavelengths when its
atoms return from an excited state to a lower energy state. By detecting and analyzing
these wavelengths, the elemental composition of a sample can be determined in accordance
with a calibration curve, thereby showing the relationship between the spectral intensity
ratio and the concentration of the element in the standard sample.
[0052] The spectral light may be produced by irradiation with electromagnetic radiation,
such as by a laser or x-rays, but is generally produced for optical emission spectroscopy
by a short spark produced by a spark generator incident upon the target of which knowledge
of its elemental composition is desired. In this case, the target is the sample, in
particular the analysis surface of the sample. Spark generators, their intensity and
their pulse regime vary according to the specific optical emission spectroscopy equipment.
Irrespective of the spark energy input, the accuracy and reliability of such optical
emission spectrometers has been known to be dependent on the accuracy and quality
of the detector and optics used to receive the radiation emitted from the sample and
the homogeneity of the sample itself.
[0053] The optical emission spectroscopy analysis procedure begins with the conductive sample
being positioned with its analysis surface face down on a predetermined region of
the stage of the analysis instrument, namely an optical emission spectrometer. More
particularly, the sample is positioned so as to span and close the analysis opening
of the spectrometer and an anode nearly abuts the analysis surface of the sample.
Once the desired positioning of the sample and proximity of the anode and analysis
surface is achieved, a spark is discharged between the anode, which is often referred
to as contact electrode, and the conductive metal sample which is electrically connected
to the spectrometer stage. This connection is, in most cases, made by gravitational
force in combination with a small load, e.g. a push rod. An optical detector receives
the emitted light from the excavated material of the analysis surface. The spark chamber,
formed in part by the space between the anode and the sample, can be continuously
purged with argon or other inert gas to avoid air ingress which would lead to erroneous
analysis values.
[0054] In an example, the apparatus comprises means to apply a purge gas to the analysis
surface of the sample for removing loosely attached particles.
[0055] For example, the means to apply a purge gas can comprise a gas nozzle arranged between
the demolding position and the analysis position. In one example, the gas nozzle can
be arranged inside the cabinet at the opening for the sample housing to enter the
cabinet and can further be adapted to apply a short gas purge to the analysis surface
of the sample when the sample housing is moved past the gas nozzle to remove loosely
attached particles from the sample.
[0056] The invention also relates to a system for demolding and analyzing a direct analysis
sample comprising:
an apparatus according to any of the preceding claims; and
a direct analysis sample formed from a molten metal material contained within a sample
chamber assembly and comprising at least a sample housing, a cover plate and closing
means, wherein a ratio of a mass of the sample housing to a mass of the molten metal
solidified in the sample housing is higher than 5, preferably higher than 9.
[0057] Also, the invention relates to a method for demolding and analyzing a direct analysis
sample formed from a molten metal material within a sample chamber assembly and comprising
at least a sample housing, a cover plate and closing means, comprising the steps:
holding and transporting the sample housing at least between a sample demolding position
and an analyzing position, wherein the sample demolding position and the sample analysis
position are different from each other;
removing the closing means to expose at least part of an analysis surface of the sample
in the sample demolding position; and
analyzing the analysis surface of the sample in the analysis position by analyzing
means located inside a cabinet after transporting the sample housing from the demolding
position through an opening in the cabinet into the analysis position.
[0058] In an example, the step of holding and transporting comprises:
holding the sample housing between a first clamp and a second clamp to stop movement
of the sample housing in at least a forward and backward direction.
[0059] In an example, the step of removing the closing means comprises:
moving at least one moveably arranged blade in at least a sideways direction or a
longitudinal direction relative to the first and second clamp:
- (i) over a surface of the sample chamber assembly to remove the closing means of the
sample chamber assembly, preferably a clamp or a brace, holding the sample housing
and the cover plate together, or
- (ii) over a surface of the sample chamber assembly to remove the closing means and
to penetrate the sample chamber assembly, preferably at a location between the sample
housing and the cover plate, to remove the cover plate from the sample housing, to
expose at least part of the analysis surface of the sample, and
moving a supporting surface in at least the sideways direction to allow the cover
plate to separate from the sample housing by means of gravitational force.
[0060] In another example, the step of holding and transporting the sample housing comprises:
holding and transporting the sample housing, after removing the closing means and
cover plate, with the analysis surface of the sample spaced from surrounding objects
such that the analysis surface of the sample is held and transported contact, abrasion
and/or friction free.
BRIEF DESCRIPTION OF THE DRAWINGS
[0061] The following schematic drawings show aspects of the invention for improving the
understanding of the invention in connection with some exemplary illustrations, wherein
- Figures 1 a - 1 c
- show schematic views of a sample chamber assembly;
- Figure 2
- shows a schematic view of an apparatus for demolding and analyzing a direct analysis
sample according to an embodiment of the invention;
- Figures 3a - 3d
- show schematic views of the transporting means and the demolding means with the actuation
means in a first position according to embodiments of the invention;
- Figure 4
- shows a schematic view of the demolding means with the actuation means between the
first position and a second position according to an embodiment of the invention;
- Figure 5
- shows a schematic view of the demolding means with the actuation means in the second
position according to an embodiment of the invention;
- Figures 6a - 6d
- show schematic views of the transporting means, the demolding means, and the analysis
means according to an embodiment of the invention; and
- Figures 7a, 7b
- show schematic views of an apparatus for demolding and analyzing a direct analysis
sample comprising a first dust cover and a second dust cover according to an embodiment
of the invention.
DETAILED DESCRIPTION
[0062] The sample chamber assembly 100 which is shown in figure 1a comprises a sample housing
101, a cover plate 103 and closing means 105.
[0063] In the shown embodiment, the cover plate 103 has the same width and length as the
sample housing 101 and forms together with the sample housing 101, the sample cavity,
while being held together by the closing means 105, which is shown as a clamp in figure
1a. The closing means 105 has a compression force sufficiently high to resist a tendency
of the sample housing 101 and cover plate 103 to separate due to the force of molten
metal flowing into the sample housing 101 and filling the sample cavity.
[0064] Figure 1b shows the sample chamber assembly 100 of figure 1a having the cover plate
and clamp removed. In the shown example, at least the part of the sample cavity 107
that is formed in the sample housing 101 can be seen.
[0065] The sample chamber assembly 100 shown in figure 1c can be the sample chamber assembly
of any of the preceding figures 1a and/or 1b. However, the sample cavity is filled
with metal, which froze against the cover plate, and thereby formed the analysis surface
109 of the direct analysis sample, which is the surface that can be analyzed by the
analyzing means.
[0066] Figure 2 shows a schematic view of an apparatus 1 for demolding and analyzing a direct
analysis sample according to an embodiment of the invention.
[0067] Analyzing means 7 are located inside a cabinet 3 for analyzing the analysis surface
of the sample. In the shown embodiment, the cabinet 3 has a rectangular ground section
and a triangular top section and can be placed on the shop floor of a steel plant.
In embodiments, not shown herein, the cabinet can have a different outer shape. The
shown analyzing means 7 is realized in the shown embodiment by a top-loaded optical
emission spectrometer. The cabinet 3 also comprises an opening 5 for the sample housing
to enter the cabinet 3. The opening 5 can be arranged in the shell of the cabinet
at a height convenient for an operator to place the sample chamber assembly into the
apparatus 1.
[0068] The transporting means 9 are shown in figure 2 in a demolding position, wherein part
of the transporting means 9 is arranged in the opening 5.
[0069] Also shown in figure 2 is a slider system 12 which comprises a glide surface/track
or slide cam, and which allows the transporting means 9 to move on between the demolding
position and an analysis position.
[0070] Figure 2 further shows demolding means 11 for removing the closing means of the sample
chamber assembly to expose the analysis surface of the sample. In the shown embodiment,
the demolding means 11 comprises a blade 13, a supporting surface 15 and actuation
means 17 which comprises in the shown embodiment a hand gear for moving the blade
13 and the supporting surface 15 between a first and a second position. Alternatively,
in an embodiment not shown herein, the blade and the supporting surface can be also
moved pneumatically or electrically. In the shown embodiment a collection bin 19 is
arranged at the outside of the cabinet 3 for collecting the removed closing means
and cover plates.
[0071] Figures 3a, 3b show schematic views of the transporting means 9 and the demolding
means 11 with the actuation means 17 in a first position. In the shown embodiment
the transporting means 9 comprises a first clamp 23a and a second clamp 23b that hold
the sample housing 101 and stop movement of the sample housing 101 in a forward and
a backward direction. Here, the term 'forward direction' can be defined by referring
to transporting the sample housing 101 from the demolding position, in which it is
shown in figure 3a, through the opening 5 into the cabinet 3. The term backward direction'
can be defined by referring to the opposite direction. The first clamp 23a and the
second clamp 23b that hold the sample housing 101 can also stop movement of the sample
housing 101 in a sideways direction relative to the forward and backward direction.
[0072] In the shown embodiment the first clamp 23a and the second clamp 23b are movably
arranged in the forward and backward direction for transporting the sample housing
101 between the sample demolding position and the sample analysis position. As shown
in figure 3a, the first clamp 23a and the second clamp 23b holding the sample housing
101 move together in one direction. However, in an embodiment not shown herein, the
first clamp and the second clamp can move independently from each other.
[0073] Also shown in figure 3a are sensor means 25 on the first clamp 23a for detecting
contact of the first clamp 23a and the sample housing 101. In another not shown embodiment,
both the first and second clamp could comprise sensor means.
[0074] For demolding, the blade 13 associated with the actuation means 17 moves over the
surface of the sample housing 101 to get hold of at least part of the closing means
105 and to remove it from the sample housing 101 while the blade 13 moves into the
second position as shown in the following figures. The demolding means 11 also comprises
a supporting surface 15 on which at least part of the cover plate 103 rests on prior
to demolding in the first position of the actuation means 17.
[0075] When the actuation means 17 moves from the first position into the second position,
the supporting surface 15 moves away from the cover plate 103 so that the cover plate
103 can separate from the sample housing 101 by means of gravitational force and can
drop through an aperture 27, which can be best seen in figure 3d, arranged next to
the supporting surface 15 to expose the analysis surface of the sample. In the shown
embodiment removing the closing means 105 and moving away the supporting surface 15
takes place in a sequential order.
[0076] Figure 3b shows a schematic top view of the transporting means 9 and the demolding
means 11 with the actuation means 17 in the first position. In addition to the components
already shown in the previous figure, an abutment surface 21 and the collection bin
19 for collecting the removed closing means 105 and cover plate 103 are depicted.
The abutment surface 21 is arranged to prevent movement of the sample housing 101
in the sideways direction during demolding. However, the abutment surface 21 is merely
optional, since the first clamp 23a and the second clamp 23b can be designed to prevent
movement of the sample housing 101 in the forward/backward and sideways direction
during demolding.
[0077] In an example, the transporting means 9 comprises the abutment surface 21 arranged
at least in part parallel to the second clamp 23b to prevent movement of the sample
housing 101 in a sideways direction by wedging the sample housing 101 between the
abutment surface 21 and the first clamp 23a and second clamp 23b. The abutment surface
21 can be rigidly arranged, for example on the cabinet, relative to the demolding
means 11, wherein the distance between abutment surface 21 and the first and/or second
clamp 23a, 23b can be chosen to match the width of the sample housing 101.
[0078] Figures 3c and 3d show an embodiment of the invention, where the second clamp 23b
comprises locking means 24 realized by a spring biased latch which allows the sample
housing 101 to be moved past the locking means 24 towards the first clamp 23a for
inserting the direct analysis sample into the apparatus. Once the sample housing 101
was moved past the locking means 24, the locking means 24 prevents movement of the
sample housing 101 in the opposite direction, i.e. in a direction away from the first
clamp 23a. Also, as shown in figure 3d, the aperture 27 is an aperture, through-hole,
or passage opening in the material of the supporting surface 15 which is dimensioned
to allow the cover plate to fall through.
[0079] Figure 4 shows a schematic view of the demolding means 11 with the actuation means
17 between the first position and a second position according to an embodiment of
the invention. As already described with reference to figures 3a - 3d, the demolding
can take place sequentially, where the blade 13 removes the closing means 105 from
the sample housing 101 in a first step. When the actuation means 17 is moved further
towards the second position, the supporting surface 15 is not any longer supporting
the cover plate 103. So, the cover plate 103 separates from the sample housing 101
and drops through the aperture, shown in figure 3d, into the collection bin 19 shown
in figure 5.
[0080] Figures 6a - 6d show schematic views of the transporting means 9, the demolding means
11, and the analysis means 7 according to an embodiment of the invention. In figure
6a, the demolding means 11 is in the first position as already shown in figures 3a
and 3b. The transporting means 9 is in the demolding position to allow the demolding
means 11 to remove the closing means 105 and to expose the analysis surface of the
sample. Figure 6b shows the demolding means 11 in the second position as already shown
in figure 5. The analysis surface of the sample (not shown) is now exposed and is
ready for transport from the demolding position into the analysis position along an
axis extending from a sample bay, where the sample is inserted (which can be the demolding
position) to the analysis means / analysis position.
[0081] In the shown embodiment, the demolding position is the same position as an inserting
position where the sample is inserted into the transporting means 9. In an alternative
embodiment (not shown in here), the demolding position and the inserting position
can be different positions where the sample is transported between the inserting position,
the demolding position, and the analysis position.
[0082] Figure 6c shows the transport of the sample housing 101 from the demolding position
into the analysis position. As depicted, the sample housing 101 is transported having
its analysis surface directed towards a contact electrode of the analysis means 7,
which comprises in the shown embodiment an optical emission spectrometer, while being
held by the transporting means 9. For transporting the sample housing 101, the transporting
means 9 comprises drive means 10 such as an electric motor, a pneumatic drive, or
a manual drive to move the transporting means 9 on a slider system 12 such as the
shown glide surface/track or slide cam between the demolding position and the analysis
position. For example, a position sensor connected to a controlling unit (both position
sensor and controlling unit are not shown in figures 6a - 6c) can detect that the
actuation means 17 was brought into the second position, which triggers the controlling
unit to activate the drive means 10. As it can be seen, the sample housing 101 is
transported with the analysis surface of the sample spaced from surrounding objects
such that the analysis surface of the sample is held and transported contact, abrasion
and/or friction free.
[0083] In the shown embodiment the apparatus also comprises means to apply purge gas 20
to the analysis surface of the sample for removing loosely attached particles. The
means to apply purge gas 20 comprise a gas nozzle arranged between the demolding position
and the analysis position. As shown, the gas nozzle is arranged inside the cabinet
at the opening for the sample housing 101 to enter the cabinet and is adapted to apply
a short gas purge to the analysis surface of the sample when the sample housing 101
is moved past the gas nozzle to remove loosely attached particles from the analysis
surface.
[0084] Once the transporting means 9 has arrived in the analysis position, as shown in figure
6d, the controlling unit can trigger the analysis means 7 to analyze the analysis
surface of the sample.
[0085] In the embodiment shown in figures 6a - 6d, the analysis means 7 comprises a top-loaded
optical emission spectrometer comprising a spring 28 to hold the analysis surface
of the sample at a distance to a contact electrode 26 of the optical emission spectrometer,
and which is adapted to establish an electric contact to the analysis surface of the
sample when the spring 28 is in a compressed state.
[0086] The spring 28 has a spring force sufficiently high to push the sample housing 101
containing the sample away from a contact surface 22 of the optical emission spectrometer.
This allows to rearrange the analysis surface on the contact surface 22 for moving
the sample to different analysis spots on the analysis surface for a plurality of
analysis or just one more analysis after the first analysis was done. The shown setting
prevents contact of the analysis surface of the sample with materials that might contaminate
the analysis surface. Figures 6a - 6d also show that the optical emission spectrometer
comprises a push rod 30 to push the sample housing 101 with the analysis surface first
onto the contact surface 22 of the optical emission spectrometer to establish an electrical
contact between the analysis surface and the contact electrode 26.
[0087] Figures 7a and 7b show schematic views of an apparatus 1 for demolding and analyzing
a direct analysis sample comprising a first dust cover 29a and a second dust cover
29b according to an embodiment of the invention.
[0088] In the shown embodiment, the first dust cover 29a is mounted on a stationary part
of the apparatus 1, and the second dust cover 29b is mounted on the blade or on a
moveable part mechanically associated with the blade and moving together with the
blade when the actuation means is 17 is moved from the first position into the second
position and vice versa. The first dust cover 29a comprises an insertion-opening 31
for inserting the sample chamber assembly into the transporting means. As shown in
figure 7b, the second dust cover 29b overlaps the insertion-opening 31 when the actuation
means 17 is in the second position.
[0089] The features disclosed in the claims, the specification, and the drawings may be
essential for different embodiments of the claimed invention, both separately or in
any combination with each other.
Reference Signs
[0090]
- 1
- Apparatus for Demolding and Analyzing
- 3
- Cabinet
- 5
- Opening
- 7
- Analyzing Means
- 9
- Transporting Means
- 10
- Drive Means
- 11
- Demolding Means
- 12
- Slider System
- 13
- Blade
- 15
- Supporting Surface
- 17
- Actuation Means
- 19
- Collection Bin
- 20
- Means to Apply Purge Gas
- 21
- Abutment Surface
- 22
- Contact Surface
- 23a, 23b
- First Clamp, Second Clamp
- 24
- Locking Means
- 25
- Sensor Means
- 26
- Contact Electrode
- 27
- Aperture
- 28
- Spring
- 29a, 29b
- Fist Dust Cover, Second Dust Cover
- 30
- Push Rod
- 31
- Insertion Opening
- 100
- Sample Chamber Assembly
- 101
- Sample Housing
- 103
- Cover Plate
- 105
- Closing Means
- 107
- Sample Cavity
- 109
- Analysis Surface
1. Apparatus for demolding and analyzing a direct analysis sample formed from a molten
metal material contained within a sample chamber assembly, wherein the sample chamber
assembly comprises at least a sample housing, a cover plate and closing means, comprising:
a cabinet defining an interior and comprising at least one opening for the sample
housing to enter the cabinet, and analyzing means located inside the cabinet for analyzing
an analysis surface of the sample;
demolding means adapted to remove at least the closing means to expose at least part
of the analysis surface of the sample; and
transporting means adapted to hold and transport the sample housing at least between
a sample demolding position, where the closing means is removed by the demolding means,
and a sample analysis position, where the analysis surface of the sample is analyzed
by the analyzing means, and wherein the sample demolding position and the sample analysis
position are different from each other.
2. Apparatus according to claim 1, wherein the demolding means comprises at least one
blade arranged, preferably moveably arranged, in at least a sideways direction or
a longitudinal direction relative to an axis formed by the demolding position and
the analysis position and adapted:
(i) to move over a surface of the sample chamber assembly to remove the closing means
of the sample chamber assembly, preferably a clamp or a brace, holding the sample
housing and the cover plate together, or
(ii) to move over a surface of the sample chamber assembly to remove the closing means
and to penetrate the sample chamber assembly, preferably at a location between the
sample housing and the cover plate to remove the cover plate from the sample housing,
to expose at least part of the analysis surface of the sample.
3. Apparatus according to claim 1 or 2, wherein the demolding means comprises at least
one supporting surface to support at least a part of the cover plate of the sample
chamber assembly when being held by the sample transporting means and wherein the
supporting surface is movably arranged to allow the cover plate to separate from the
sample housing by means of gravitational force.
4. Apparatus according to any of claims 1 to 3, wherein the transporting means comprises:
a first clamp and a second clamp for holding the sample housing and to stop movement
of the sample housing in at least a forward and a backward direction from both the
demolding position and analysis position, wherein the first clamp and the second clamp
are movably arranged in the forward and backward direction for transporting the sample
housing between the sample demolding position and the sample analysis position, wherein
the second clamp is arranged at least in part opposite the first clamp, preferably
the first clamp or the second clamp further comprises sensor means for detecting contact
of the first clamp or the second clamp and the sample housing.
5. Apparatus according to claim 4, wherein the second clamp comprises locking means,
preferably a spring biased latch, adapted to allow the sample housing to be moved
past the locking means towards the first clamp, and to prevent movement of the sample
housing in the opposite direction, preferably the first clamp comprises another locking
means, preferably another spring biased latch, adapted to prevent movement of the
sample housing in the forward and backward direction.
6. Apparatus according to any of claims 2 to 5, wherein the demolding means comprises
actuation means for moving, preferably sequentially moving, the blade and the supporting
surface, and wherein the actuation means comprises a hand gear for moving the blade
and the supporting surface mechanically, or a push rod for moving the blade and the
supporting surface pneumatically or electrically, between a first and a second position.
7. Apparatus according to any of claims 2 to 6, wherein the actuation means is adapted
to be moved between a first and a second position, wherein:
in the first position, the actuation means and blade are arranged for loading the
sample housing, wherein at least the first clamp is at least partly arranged in the
opening of the sealed cabinet, and
in the second position, the actuation means and blade are arranged for analyzing the
sample by the analyzing means, wherein at least the second clamp is at least partly
arranged in the opening of the sealed cabinet.
8. Apparatus according to claim 7, comprising:
at least a first dust cover mounted on a stationary part of the apparatus, and a second
dust cover mounted on the blade or a moveable part mechanically associated with the
blade and moving together with the blade, wherein at least part of the first dust
cover and the second dust covers are arranged to be spaced apart to allow loading
the sample chamber assembly when the actuation means is in the first position, and
at least partly overlap when the actuation means is in the second position, preferably
at least one dust seal is arranged on one of the first and/or second dust covers to
seal a remaining space between the first and second dust cover when they are overlapping.
9. Apparatus according to claim 8, wherein the first dust cover comprises an insertion-opening
for inserting the sample chamber assembly into the transporting means, and wherein
the second dust cover overlaps the insertion-opening when the actuation means is in
the second position.
10. Apparatus according to any of the preceding claims, wherein the analyzing means comprise
an optical emission spectrometer, preferably a spark optical emission spectrometer,
more preferably a top-loaded optical emission spectrometer comprising a spring to
hold the analysis surface of the sample at a distance to a contact electrode of the
optical emission spectrometer, and adapted to establish an electric contact to the
analysis surface of the sample when the spring is in a compressed state, most preferably
a top-loaded optical emission spectrometer comprising a spring having a force of less
than 100 Newton, preferably less than 10 Newton to hold the analysis surface at a
distance of preferably less than 1 mm to the contact electrode of the optical emission
spectrometer.
11. System for demolding and analyzing a direct analysis sample comprising:
an apparatus according to any of the preceding claims; and
a direct analysis sample formed from a molten metal material contained within a sample
chamber assembly and comprising at least a sample housing, a cover plate and closing
means, wherein a ratio of a mass of the sample housing to a mass of the molten metal
solidified in the sample housing is higher than 5, preferably higher than 9.
12. Method for demolding and analyzing a direct analysis sample formed from a molten metal
material contained within a sample chamber assembly and comprising at least a sample
housing, a cover plate and closing means, comprising the steps:
holding and transporting the sample housing at least between a sample demolding position
and an analyzing position, wherein the sample demolding position and the sample analysis
position are different from each other;
removing the closing means to expose at least part of an analysis surface of the sample
in the sample demolding position; and
analyzing the analysis surface of the sample in the analysis position by analyzing
means located inside a cabinet after transporting the sample housing from the demolding
position through an opening in the cabinet into the analysis position.
13. Method according to claim 12, wherein holding and transporting comprises:
holding the sample housing between a first clamp and a second clamp to stop movement
of the sample housing in at least a forward and backward direction.
14. Method according to claim 13, wherein removing the closing means comprises:
moving at least one moveably arranged blade in at least a sideways direction or a
longitudinal direction relative to the first and second clamp:
(i) over a surface of the sample chamber assembly to remove the closing means of the
sample chamber assembly, preferably a clamp or a brace, holding the sample housing
and the cover plate together, or
(ii) over a surface of the sample chamber assembly to remove the closing means and
to penetrate the sample chamber assembly, preferably at a location between the sample
housing and the cover plate, to remove the cover plate from the sample housing, to
expose at least part of the analysis surface of the sample, and
moving a supporting surface in at least the sideways direction to allow the cover
plate to separate from the sample housing by means of gravitational force.
15. Method according to any of claims 12 to 14, wherein holding and transporting the sample
housing comprises:
holding and transporting the sample housing, after removing the closing means and
cover plate, with the analysis surface of the sample spaced from surrounding objects
such that the analysis surface of the sample is held and transported contact, abrasion
and/or friction free.